Balanced Receiver Technology Development for the Caltech Submillimeter Observatory

Kooi, J.; Chamberlin, Richard; Monje, Raquel; Force, B.; Miller, David; Phillips, T. G.

doi:10.1109/tthz.2011.2177726

Cited by 32 publications

(28 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We find between 180−280 GHz a front-end equivalent noise temperature (T rf ) of 18−21 K and between 390−520 GHz a front-end equivalent noise temperature of 8−9 K. These losses include vignetting and spillover and are considerably worse for the 230 receiver then the 460 receiver due to the fast optics. In addition the AR coated HDPE pressure window was optimized for the 460 GHz atmospheric band [1]. A detailed breakdown of the noise budget at three frequencies across the mixer band is provided in Tables V II & V III. In Fig.…”

Section: Heterodyne Results and Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Performance of the Caltech Submillimeter Observatory Dual-Color 180–720 GHz Balanced SIS Receivers

Kooi

Chamberlin

Monje

et al. 2014

IEEE Trans. THz Sci. Technol.

View full text Add to dashboard Cite

We report on balanced SIS receivers covering the astronomical important 180−720 GHz submillimeter atmospheric window. To facilitate remote observations and automated spectral line surveys, fully synthesized local oscillators are employed. High-current-density Nb-AlN-Nb superconductinginsulating-superconducting (SIS) tunnel junctions are used as the mixing element. The measured double-sideband (DSB) 230 GHz receiver noise temperature, uncorrected for optics loss, ranges from 50 K at 185 GHz, 33 K at 246 GHz, to 51 K at 280 GHz. In this frequency range the mixer has a DSB conversion gain of 0 ± 1.5 dB. The measured 460 GHz doublesideband receiver noise temperature, uncorrected for optics loss, is 32 K at 400 GHz, 34 K at 460 GHz, and 61 K at 520 GHz. Similar to the 230 GHz balanced mixer, the DSB mixer conversion gain is 1 ± 1 dB. To help optimize performance, the mixer IF circuits and bias injection are entirely planar by design. Dual-frequency observation, by means of separating the incoming circular polarized electric field into two orthogonal components, is another important mode of operation offered by the new facility instrumentation. Instrumental stability is excellent supporting the LO noise cancellation properties of the balanced mixer configuration. In the spring of 2012 the dual-frequency 230/460 SIS receiver was successfully installed at Caltech Submillimeter Observatory (CSO), Mauna Kea, HI.Index Terms-Superconducting-Insulating-Superconducting (SIS) mixer, balanced mixers, amplitude noise rejection, Wilkinson in phase power combiner, AlN tunnel barrier, heterodyne receiver, high-current-density, multiple Andreev reflection (MAR), broadband waveguide transition, system stability, Allan variance, synthesized local oscillator (LO), quantum noise limit.

show abstract

Section: Heterodyne Results and Discussionmentioning

confidence: 99%

“…It is of interest therefore to establish the actual vs. modeled noise rejection. It should be noted that a second, and possibly equally important, motivation for balanced mixers is the efficiency with which the local oscillator carrier signal may be injected [1].…”

Section: Spurious Signal and Amplitude Noise Rejectionmentioning

confidence: 99%

Performance of the Caltech Submillimeter Observatory Dual-Color 180–720 GHz Balanced SIS Receivers

Kooi

Chamberlin

Monje

et al. 2014

IEEE Trans. THz Sci. Technol.

View full text Add to dashboard Cite

show abstract

“…The balanced receiver scheme offers several advantages over the single-ended mixer configuration such as all available LO power can be utilized and it ideally provides immunity to amplitude modulations from the LO source [33], which is predominantly limiting the stability of HEB receivers [34]. However, the balanced configuration is more complex than its single-ended counterpart and comprises of a RF hybrid, which combines the RF and LO single, two HEB mixers, which ideally exhibit identical electrical properties, and an in-phase IF combiner [30].…”

Section: Balanced Waveguide Heterodyne Receiver At 13 Thzmentioning

confidence: 99%

Suspended GaN beams and membranes on Si as a platform for waveguide-based THz applications

Krause

Desmaris

Pavolotsky

et al. 2018

J. Micromech. Microeng.

View full text Add to dashboard Cite

Epitaxial growth of ultra-thin NbN films on AlxGa1-xN buffer-layers S Krause, D Meledin, V Desmaris et al. IntroductionThe exploration of the THz frequency range is constantly gaining speed and numerous applications have emerged within research, security, astronomy, biomedicine and metrology in recent years [1][2][3]. The main reason for this relatively late development can be attributed to several technological challenges that had to be overcome. As the dimensions of microwave components usually scale with the wavelength, their size presents a serious issue when the device operation frequency is approaching the THz range. This manifests itself in certain performance limitations due to parasitic capacitances, thermal issues, the excitation of unwanted electromagnetic (EM) modes or excessive RF losses in conductors as the skin depth may approach the roughness of the metal surface. Waveguides for guiding THz EM waves offer wideband operation and full confinement of the fields, yet they are also miniaturized and demand high surface quality and accuracy on the waveguide dimensions and alignment. Several different micro fabrication techniques [4] were developed for this purpose and are based on copper electroforming over a thick sacrificial photo resist mold [5,6] or deep Si etching processes [7]. In waveguidebased THz components, the actual substrate becomes more of a delicate membrane-like structure, which reduces the electrical loading of the waveguide and excludes substrate modes. However, it is difficult to manipulate and to place such beams suspended inside the waveguide with high alignment precision. Typically beam leads [8] made of thick electro-plated gold are used for the electrical contacting, however, once the device is mounted it can neither be modified nor removed in a non-destructive matter. One possible approach to overcome the aforementioned issues is based on a Π-shaped Si support frame holder [9], which keeps a thin Si membrane hosting the active device suspended. This concept has been successfully AbstractWe demonstrate the suitability of employing suspended GaN beams on a Π-shaped Si frame for waveguide-based cryogenic THz components and systems. This concept addresses major challenges and provides eased device handling, cryogenic operation, micron-alignment possibilities, high integratability and allows the electrical contacting by using bonding wires. In particular, a balanced hot electron bolometer (HEB) mixer was implemented for frequencies at 1.3 THz with state-of-the-art IF performance, which combines micro-machined all-metal waveguide components in conjunction with a suspended GaN beam. In addition, in order to accomplish a proper design of active or passive components, the accurate knowledge of the effective dielectric constant at THz frequencies is crucial when such membranes are employed. Thus, a direct measurement method based on a resonance structure and an S-parameter measurement between 1 THz and 1.5 THz is also presented.Keywords: THz components, GaN on Si, HEB, waveguide (Some f...

show abstract

“…The isolation of the balanced mixer depends on the amplitude and phase balance of the different components. The LO sideband noise rejection ratio (LNR) has been defined to express the performance of the balanced mixer [12]. The LNR was simply estimated by the quotient of the conversion losses measured at the two IF output ports [13].…”

Section: Port3 Port4mentioning

confidence: 99%

Short-slot Hybrid Coupler Using Linear Taper in W-band

Kuroiwa

González

Koyano

et al. 2013

J Infrared Milli Terahz Waves

View full text Add to dashboard Cite

-We have designed and fabricated a broadband short-slot hybrid coupler using a twostage linear taper in W-band. The coupler consists of two metal pieces split at the edge of the narrow wall of the waveguide, which makes it possible to use simple direct machining for fabrication. The electrical performance of the coupler was measured by a Vector Network Analyzer (VNA) at room temperature. The results showed excellent performance as designed: amplitude imbalance between the two output ports of ≤ 1 dB, phase difference between the output ports with respect to 90°< 3°, input return loss < -15 dB, and isolation < -15 dB across the measured frequency range of 85-110 GHz. The short-slot hybrid coupler was used in a balanced Superconductor-Insulator-Superconductor (SIS) mixer at 4 K. The noise performance was almost the same as that of the two single-ended mixers used in the balanced mixer. These results indicate that our short-slot hybrid coupler has great potential for practical applications, such as at millimeter-and submillimeter-waves.

show abstract

Balanced Receiver Technology Development for the Caltech Submillimeter Observatory

Abstract: Abstract-The

Cited by 32 publications

References 20 publications

Performance of the Caltech Submillimeter Observatory Dual-Color 180–720 GHz Balanced SIS Receivers

Performance of the Caltech Submillimeter Observatory Dual-Color 180–720 GHz Balanced SIS Receivers

Suspended GaN beams and membranes on Si as a platform for waveguide-based THz applications

Short-slot Hybrid Coupler Using Linear Taper in W-band

Contact Info

Product

Resources

About